Transfer system

ABSTRACT

A transfer apparatus for transferring objects from a first location to a second location includes a transfer device adapted to be coupled to a lifting device. The transfer device comprises an outer structure which defines an inner space in which an object to be transferred may be located and securing device is provided to secure the object to the transfer device during transfer.

This invention relates to the transfer of personnel and/or equipment,for example between vessels at sea. Existing methods of achievingtransfer have significant limitations in terms of safety andpracticality. Such operations are particularly sensitive to weather.This invention offers a system which reduces the risks associated withtransfer in a range of weather conditions.

In this field it is already known that there are several methods oftransfer, which include those outlined below.

The main method currently used for transfer of personnel betweenoffshore oil rigs and support vessels is a rigid bottomed rope basket.The basket is usually transferred using a crane line.

This has the disadvantage that personnel are not secured in the basketand are not protected in any way from lateral or vertical impact duringlifting, setting down or in transit.

As it swings over the vessel moving with sea swell, the crane hook andlifting gear presents serious risk to personnel on the support vessel.Furthermore, there is no contingency to protect personnel in the eventof accidental immersion or severance.

Due to the perceived hazards of this type of transfer it is no longergenerally used in open water in the UKCS (United Kingdom continentalshelf), but it is used between vessels in sheltered water.

A second method of transfer is a ladder transfer. In this method thesmaller craft draws alongside the larger craft and personnel aretransferred by means of a ladder on the side of the larger craft. Due tothe relative motions of the vessels at sea, this requires personnel to"hop" across at an opportune moment.

This has the disadvantage that it is highly weather constrained andgenerally precarious in terms of safety.

A third method of transfer is a breeches buoy system. This is atraditionally used system for transferring personnel or equipmentbetween marine vessels. It is mainly utilised in rescue operations.

This has the disadvantage that the transfer is generally precarious addis vulnerable to operator error.

In accordance with a first aspect of the present invention, apparatusfor transferring objects from first location to a second locationcomprises a transfer device adapted to be coupled to a lifting device,the transfer device comprising an outer structure which defines an innerspace in which an object to be transferred may be located and securingmeans to secure the object to the transfer device during transfer.

Typically, the object may be a person and the securing means couldcomprise a seat and/or a harness. Preferably, the harness is a full bodyharness.

Preferably, the outer structure could be in the form of a cage which istypically substantially rigid to help protect the object beingtransferred.

Typically, the first and/or the second location could be a floatingstructure.

Preferably, where a part of the transfer is over water, the transferdevice may also include buoyancy means. Typically, the transfer devicemay be designed to be self-righting.

Typically, the transfer device may further include shock absorbing meansfor absorbing impacts of the transfer device with other objects. Theshock absorbing means may include shock absorbers on the base of theouter structure to absorb the shock of landing at the first and/orsecond locations. The securing means could also be mounted in the outerstructure by shock absorbing means to help reduce the effects ofaccidental or deliberate collision on the object being transferred.Furthermore the transfer device may include a shock absorbing couplingto couple the transfer device to the lifting device.

Preferably, the apparatus may also include a guide line coupled to thetransfer device which may be used to guide the transfer device to thesecond location.

Typically, the lifting device is a crane.

In accordance with a second aspect of the present invention, atransporting device comprises a base section and a number of side walls,the side walls extending from the base to a common apex, the basesection and the side walls defining an interior space in which an objectmay be located.

Preferably, the base is in the form of a polygon, and side walls extendfrom each side of the polygon.

Typically, the shape defined by the base section and side walls isgenerally the shape of a pyramid and is preferably a triangular pyramid.

Preferably, the transporting device is adapted to transport humanpersonnel and may typically include a seat and restraining means withinthe interior space.

Preferably, the transporting device is positively buoyant where it isintended to use on water or near water.

Typically, the transporting device may have a self-righting capabilityin water. Preferably, the transporting device may include a keel in orbelow base section to enhance the self-righting performance of thetransporting device.

Preferably, the common apex is coincident with a vertical axis throughthe centre of the base section.

Typically, the base section may include shock absorbing means, and thedevice may include attachment means, typically adjacent to or at thecommon apex to permit the transporting device to be lifted.

Examples of a transfer system in accordance with the invention will nowbe described with reference to the accompanying drawings, in which:

FIG. 1 is a schematic view of a transfer system having a first exampleof a transfer capsule in use between two vessels;

FIGS. 2a and 2b are a side view and a top view, respectively of thefirst example of the transfer capsule shown in FIG. 1;

FIG. 3 is a cross sectional view of a lifting assembly on the transfercapsule of FIGS. 2a and 2b;

FIGS. 4a and 4b are a side cross-sectional view and a plancross-sectional view of the transfer capsule of FIGS. 2a and 2b, in use;

FIG. 5 is a schematic view of a transfer system having a second exampleof a transfer capsule, the system being used for transferring objectsfrom a fixed structure to a vessel;

FIG. 6 is a front elevation of the second example of the transfercapsule in FIG. 5, showing a suspension system;

FIG. 7 is a front elevation, similar to FIG. 6 but with the suspensionsystem not omitted;

FIG. 8 is cross-sectional view through the top of the second example ofthe transfer capsule;

FIG. 9 is a front elevation showing the second transfer capsule in afirst use;

FIG. 10 is a top cross-sectional view showing the second transfercapsule in the first use;

FIG. 11 is a front elevation showing the second transfer capsule in asecond use;

FIG. 12 is a top cross-sectional view showing the second transfercapsule in the second use;

FIGS. 13a, 13b and 13c show a front elevational view, a plan view, and aview on the line AA in FIG. 13a, respectively of the seating arrangementin the second transfer capsule;

FIG. 14 is a top view of a third example of a transfer capsule;

FIG. 15 is side elevation of the third transfer capsule shown in FIG.14;

FIG. 16 is partial cross-sectional view of the third capsule on the lineAA of FIG. 14; and,

FIG. 17 is a bottom view of the third transfer capsule.

A first example of a transfer system is shown in FIG. 1 and consists ofa first example of a transfer capsule 1 which is in the form of astructurally enclosed rigid capsule 1 offering protection to personnelor equipment during transfer between vessels at sea. The systemcomprises a crane 19 mounted on a first vessel 18, the crane can beoperated to pick up and transfer the capsule 1 using a crane hook 17.The system is provided with shock absorption and motion compensationfeatures 2, 3 to minimise the risk of damage to equipment or injury topersonnel during transfer. The capsule 1 will usually be buoyant andself-righting to minimise the risks to personnel in the event ofinadvertent immersion. The capsule 1 will generally be constructed ofmaterials which are not prone to corrosion or early deterioration.

With the rigid capsule system, the robust structure of the capsule 1 isdesigned to protect one or more passengers against injury caused bylateral loads (such as those caused by impact due to the swinging motionof a crane line 4 during the capsule transfer) or by vertical impacts(such as those occurring during lifting and setting down of the capsule1 on the deck 5 of a vessel 6). The capsule 1 is fitted with some shockabsorption system 7 (such as hydraulic cylinders, springs, air cushionsor a deformable substance like rubber) on the underside, to reduce theimpact forces imparted when the capsule 1 makes contact, for examplewith the deck 5 of the vessel 6.

The capsule 1 is fitted with means of securing passengers 10 and freight12 in a safe position during transfer, such as a full harness 9 used tosecure the passengers in a seated position. A head restraint 8 is alsoincorporated to protect the passengers 10 against whiplash. Passengerswill be protected against the effects of impact on the capsule 1 by anenergy absorbing medium such as dense foam or particular polystyrene.Alternatively, this may be achieved by suspending a seat 14 usingtensioned elements 13 in such a manner that these will dissipate theenergy of the impact.

Luggage or freight 12 will generally be secured within the capsule 1 insuch a way that it will not be dislodged in the event of any impact. Theweight and position of any item of luggage 12 will be controlled toensure that it has no adverse effect on either the buoyancy or the selfrighting characteristics of the capsule 1.

The capsule 1 is shaped and constructed to minimise the changes ofsnagging on adjacent structures during operation. For example the upwardfacing outer profile of the capsule 1 may be rounded (or egg shaped) sothat it deflects away from, rather than catches on, any parts of thevessels structure in which it comes into contact.

With the buoyancy capsule system, the capsule 1 will comprise sufficientbuoyancy to prevent personnel from becoming permanently submersed in theevent that the capsule is immersed (for example by becoming detachedfrom its lifting gear). This will be provided by some form of closedcell (water proof) foam, placed in the internal part of the capsule(shaped to accommodate the passenger as required i.e. possibly forming aseat) or mounted on the periphery of the capsule.

With the self righting capsule system, the capsule 1 is configured toprovide a self righting feature when it is immersed in water. This isachieved by ensuring that the capsule in unstable when upside down. Inthis position its centre of gravity will be above the water line and anydisplacement results in a righting moment causing the capsule to rollover and revert to its upright position.

With the compensated handling system 2, a sprung linkage 15 (such aselastomeric rope or metallic spring) is deployed between a lifting eye16 of the capsule and a crane hook 17. A safety line 90 is coupled inparallel across the spring compensator 15. The sprung linkage 15 has theeffect of maintaining tension in the lifting gear when the capsule 1 isbeing set down or picked up and therefore acts as a shock absorptionmechanism. The travel of the sprung linkage 15 is sufficient to maintaintension over the anticipated range of relative heave motion between thedecks of the vessel 6 and the vessel 18. This same mechanism alsoprevents sudden changes in lifting gear tension when the capsule 1 ispicked up, thus minimising the potential for damage caused by the ropesnagging or the capsule striking the deck of a vessel.

The use of the sprung link 15 provides motion compensation when tensionis applied to a line 3 from the vessel 6 which is connected to theunderside of the capsule (see FIG. 1). The line attached to the vessel 6maintains a fixed length (when it is not being wound in by a winch) andthe relative heave motion of the two vessels will be compensated for bythe changes in length of the sprung link 15. Tension will becontinuously applied to the capsule from above and below and thus itsdescent will be controlled with the capsule moving in sympathy with thevessel heave. Such a line 3 also improves the accuracy of landing thecapsule 1 on the vessel 6 and reduces the chances of impact due to theuncontrolled swinging of the capsule 1 close to the vessel 6.

A lightweight slinging system reduces the hazards involved in handlingheavy or rigid lifting tackle in the proximity of a vessel moving with asea swell.

The capsule will usually be buoyant and self-righting to minimise therisks of personnel in the event of inadvertent immersion.

As shown in FIG. 2, the capsule 1 has a broadly egg shaped frame 20which is constructed from six individual members 21 of 1" diameter steeltubing. Each member 21 is formed into a roughly semi-circular shape. Themembers 21 converge at the top of the capsule and are connected into abracket 22, which also allows for connection of a central lifting eye16. The assembly of the lifting eye 16 and members 21 at the top 22 isfurther detailed in FIG. 3.

As shown in FIG. 3, the members 21 are each coupled to an upper grooveddisc plate 91 and a lower grooved disc plate 92 by a retaining pin 93. Astem 94 of the lifting eye 16 passes through central apertures in theplates and is retained by two hexagonal nuts 95 and a washer 96. Anelastomer washer 97 separates the stem 94 from the ends of the members21 and also provides a spacer between the plates 91, 92.

At the base of the structure three of the members 21 are formed intolanding feet 26, while the remaining members 21 are connected to a keel27.

Horizontal members 24, also of 1" diameter steel tube, are formed into acircular shape and connected to the principal members 21 usingmechanical unions 25. These members add strength to the overallstructure as well as providing added protection. The central horizontalstructural hoop 24a is left open over one of the six segments to providean opening 30 for access.

The lower horizontal hoop member 24b forms the support for a steel meshfloor 29, which may be welded in place or attached with bolted brackets.Straps 30 fixed to the floor 29 provide for securing of luggage orfreight 12.

At the base of the capsule, three of the main tubular members 21 arebolted through onto the keel 27. The keel 27 is a flat circular plate ofsteel. As the capsule is required to be self righting in water, leadplates can be bolted onto the keel 27 to provide the appropriate turningmoment for effective self-righting.

The remaining three vertical tubular members 21 are provided with sprungfeet 26 which provide shock absorption when the capsule is landed. Thefeet 26 use spring and damping mechanisms similar to those in common usefor motorcycle and motor car suspension systems. The three feet 26 arewell spaced in an equilateral triangle, thereby providing a stable basefor the capsule to land on, even on an uneven surface.

The capsule is rendered buoyant by the addition of foam panels 31attached to the frame around the periphery of the capsule. The foampanels 31 are made by sandwiching a steel mesh between two sheets offoam. The panels 31 are fixed at the nodes 25 of the frame by tensionedwires 32 attached to the steel mesh. The function of the buoyancy is tokeep the capsule 1 afloat and to provide its self-rightingcharacteristic. Sufficient buoyant foam will be used to ensure that inthe event of immersion the passenger's upper body will remain above thewater line. The panels 31 are evenly distributed around the frame toensure the capsule 1 will be self-righting from any attitude.

The passenger seat 14 is a plastic moulding "bucket style" seatproviding head support 8 (to protect against "whiplash") and full safetyharness 9. As shown in FIG. 4, the seat 14 is secured in place by sprungtension elements 13 with shock absorption in the upper elements (abovethe seat) to provide energy dissipation in the event of a heavy landing.

The second example of a transfer system shown in FIG. 5 shows astructurally enclosed capsule 40 which is strong and may be rigid. It isspecifically shaped and fitted with buoyant material such that it willfloat in water providing support for its occupants and will tend to beself-righting in the event that it is inverted or turned on its side inwater. The shape and construction of the capsule are such that it isstrong enough to carry the personnel and freight for which it isdesigned and will withstand impacts during use.

The shape coupled with the weight and buoyancy distribution make thestructure relatively stable in water and it will tend to beself-righting in the event of capsize. The shape is also inherentlystrong and resistant to damage from impact loads. The simplicity of theshape allows economical manufacture. The capsule will offer protectionto personnel or equipment appropriate to the application for which it isdesigned whether that by as a means of escape from a vessel or as arescue aid or as part of a system for transfer between vessels at sea oras a craft for any other purpose.

The shape of the capsule is such that it has a flat, wide base, usuallybroadly in the shape of a regular polygon. The sides of the structureconverge at the top of the structure to form a single apex. The cornersof the base and the top apex may be rounded. Typically examples of theshape would be the modified tetrahedrons shown in FIGS. 6 to 12 and 14to 17.

Buoyant material is attached to the pillars or sides joining the apex tothe base. Sufficient buoyant material may also be attached elsewhere toensure that the capsule floats at an appropriate height in the waterwhen it is fully loaded according to the application for which thespecific example is designed. The capsule may be constructed fromglassfibre or other moulded plastics or may be fabricated from tubularshaped or planar sections of metal or plastic.

The capsule may be provided with a central shaft passing through the topapex and the centre of the base which is connected to the main shell ofthe capsule and provides a facility by which the capsule may be lifted.A frame may be attached to this shaft which may provide a base forseats, stretcher bearers or other structures which may be used forattaching personnel freight or luggage. This frame may be affixed to thecentral shaft in such a way as to allow it to slide up and down theshaft to allow adjustment of weight distribution when loading thecapsule. Springing, shock absorbing and motion compensating arrangementsmay also be included to provide protection from shock to passengers orfreight during deployment, recovery or transfer.

The robust structure is designed to protect the passenger against injurycaused by lateral loads (such as those caused by the capsule collidingwith an object or structure during deployment, transfer or whenotherwise in use) or by vertical impacts (such as those occurring duringlifting and setting down of the capsule on the deck of a vessel orelsewhere). The capsule may be fitted with some shock absorption system(such as hydraulic cylinders, springs, air cushions or a deformablesubstance like rubber or foam) on the underside, to reduce the impactforces imparted when the capsule makes contact, for example with thedeck of a vessel.

The capsule will generally be fitted with a means of securing passengersand freight in a safe position during transfer, deployment or generaluse, such as a full harness used to secure the passengers in a seatedposition. Luggage will generally be secured within the capsule in such away that it will not be dislodged in the event of any impact. The weightand position of passengers, luggage and freight will be controlled toensure that it has no adverse effect on either the buoyancy or theself-righting characteristics of the vessel.

The capsule is shaped and constructed to minimise the chances ofsnagging on adjacent structures during operation. For example, theupward facing outer profile of the capsule will be rounded (or eggshaped) so that it deflects away from, rather than catches on, any partsof the vessel in which it comes into contact.

Where the capsule is required to be buoyant, it will comprise sufficientbuoyancy to prevent personnel from becoming permanently submersed whenthe capsule is immersed. Usually this will be provided by some form ofclosed cell (water proof) foam, placed in the frame of the capsule ormounted on the periphery of the capsule.

It is a particular feature of the invention that buoyancy is placed atthe periphery of the capsule between the base and the apex, for exampleon the inside of pillars joining the base and apex, as this adds to theself-righting capability of the capsule and improves its stability whenfloating in water.

The capsule design is configured to provide a self-righting feature whenit is immersed in water. This is achieved by ensuring that the capsuleis unstable when upside down. In this position its centre of gravitywill be above the water line and any displacement results in a rightingmovement causing the capsule to roll over and revert to its uprightposition.

It is a particular feature of the design that the upper sections of thecapsule are made buoyant. This provides a righting force in the eventthat the capsule is inverted in water. The capsule thus tends to rollonto one side. By ensuring that there is sufficient force acting outsidethe base of the capsule to overcome any buoyant forces at the base thecapsule will tend to roll into an upright position. This force isachieved by the distribution of weight at or below the level of the baseto provide a keel. For maximum efficiency this weight is concentric withthe vertical axis passing through the centre point of the base and apexof the capsule. The specific shape of the capsule has a low centre ofgravity which greatly assists in the self-righting process.

In the second transfer system shown in FIG. 5, the arrangement of thetransfer system is essentially the same as the transfer system shown inFIG. 1. However, the transfer capsule 40 is different. The capsule 40 isshown in more detail in FIGS. 6 to 13c. The capsule 40 has an outershell 41 which is constructed from moulded glass reinforced plastic(GRP), according to established methods. The outer fibreglass skin isapproximately 10 mm thick to produce a strong monocoque construction.The outer shell 41 has a base 42 which is further reinforced with apre-formed glassfibre mesh 43.

A central steel shaft 44 passes through holes in the base and apex andis connected to the shell 41 by threading the ends of the shaft 44 andfitting washers and nuts above and below the fibreglass at both base 42and apex 45. The shaft 44 is also fitted with a lifting eye 16 at itsupper end. The shaft 44 provides a support by which the capsule 40 maybe lifted. A seating and stretcher attachment arrangement 50 is attachedto the shaft 44 and is shown in more detail in FIGS. 13a to 13c. Thecapsule 40 is also provided with a water activated light 98 which may beused as a location device if the capsule 40 becomes detached from thecrane hook 17 and lands in the water.

The capsule 40 is rendered buoyant by the addition of foam 46 attachedto the pillars 47 joining the base 42 and the apex 45 of the capsule 40.Foam (not shown) is also positioned at apex 45 itself. Additionalbuoyancy may be incorporated at the base 42 of the capsule. The functionof the buoyancy is to keep the capsule 40 afloat and to provide it withself-righting characteristics. Sufficient buoyant foam 46 is used toensure that in the event of immersion a passenger's upper body willremain above the water line. The buoyancy is evenly distributed aroundthe frame to enhance the self-righting capabilities of the capsule 40.The self-righting capabilities of the capsule 40 can be further improvedby attaching a metal disk 48 to the bottom of the shaft 44 to form asimple keel 48.

FIGS. 7 and 8 show the seating arrangement in place in the capsule 40.The seating arrangement comprises two seats 49, 50 side by side and onopposite sides of the shaft 44. A backrest 51 of one of the seats 50 ishinged 58 so that it can be folded flat to provide a platform 59 for astretcher. FIGS. 9 and 10 show the capsule 40 in use with the seats 49,50 arranged for two seated passengers. FIGS. 11 and 12 show the capsule40 in use with the backrest 51 of seat 50 horizontal so that the capsule40 may accommodate one seated passenger and one stretcher.

FIGS. 13a to 13c show the details of the seating arrangement. Acylindrical metal sleeve 61 is fixed to a frame 62 constructed fromsteel box section which forms a mounting base for the seats 49, 50. Thesleeve 61 fits closely over the shaft 44 allowing the seat base frame 62to slide but preventing excess lateral movement. A spring 63 is alsoslid over the shaft 44 between the keel 48 of the capsule 40 and thebottom of the metal sleeve 61. This provides shock absorption directlythrough the seating assembly when the capsule 40 is picked up or landed.A pneumatic or hydraulic cylindrical shock absorber 64 is fitted at oneof its ends to the seat mounting base frame 62 and at its other end to aclamp 65. The clamp 65 is in turn fitted around the shaft 44 and lockedin place. The shock absorber 64 provides a damping force which preventsuncontrolled bouncing of the seating frame 62 up and down the shaft 44.Because the shock absorber 64 is fixed to the shaft 44 and to theseating base frame 62 it also prevents the metal sleeve 61, seating baseframe 62 and seats 49, 50 from rotating relative to the shaft 44.

The seats 49, 50 are moulded plastic of glassfibre and feature highbacks to provide neck restraint. At least one of the seats 50 is hinged58 at the bottom of the seat back 51 so that the back 51 can be laidflat to provide a horizontal base onto which a stretcher can bestrapped. Base 55 of the seat 50 extends beyond its junction with theseat back 51 to provide support for the seat back 51 when it is foldedflat. The seats 49, 50 are provided with full harness seats belts 66 tohold passengers securely.

Three feet 67 are attached close to the corners of the base 42. The feet67 are made of a firm but compressible foam such as polyethylene, whichprovides shock absorption when the capsule 40 is landed. The triangulararrangement of the feet 67 ensures that the capsule 40 will be as stableas possible when standing on an uneven surface.

As in the first example of a transfer system shown in FIG. 1, a sprungmember 15 is provided in the suspension gear of the capsule 40 as shownin FIGS. 5 and 6. This allows a compensated landing system to be used,as described above for the first example of the transfer system.

When a line is attached to the lower side of the capsule 40 and tensionis applied to the line, the member 15 will expand and contract tocompensate for the variation in load on the lower line, in the samemanner as that described above for the first transfer system.

A third example of a capsule 80 for use in the transfer system is shownin FIGS. 14 to 17. The shape of the outside of the capsule 80 is shownin FIGS. 14 to 17 and is defined but not necessarily constructed asfollows:

Four identical spheres 81 are centred on the apexes of a tetrahedron.The spheres 81 are connected by sections of cylindrical pipe 82 whosediameter is equal to that of the spheres 81 and whose central axescoincide with the edges of the tetrahedron.

The capsule therefore has four faces. The plane of each face istangential to the circumference of each of the three cylindricalsections of pipe 82 which form the side of each face. One such plane isdefined as the base 83.

The outer shell 87 is constructed from moulded glass reinforced plastic(GRP), according to established methods. The outer fibreglass skin isapproximately 10 mm thick to produce a strong monocoque construction.

A central steel shaft 44 passes through holes in the base 83 and apex 84and is connected to the shell 87 by threading the ends of the shaft andfitting washers and nuts above and below the fibreglass at both base andapex. This shaft is also fitted with a lifting eye 16 at it upper end.The shaft 44 provides a support by which the capsule 80 may be lifted.The seating and stretcher attachment arrangement is also attached to thecentral shaft 44 and is as described above for the capsule 40.

The capsule is rendered buoyant by the addition of foam 9 attached tothe sections 82 joining the base 83 and apex 84 of the capsule and atthe apex itself. Additional buoyancy may by incorporated at the base ofthe capsule. The function of the buoyancy is to keep the capsule afloatand to provide its self righting characteristic. Sufficient buoyant foamwill be used to ensure that in the event of immersion the passenger'supper body will remain above the water line. The buoyancy is evenlydistributed around the frame to enhance the self-righting capabilitiesof the structure. Eccentric weight at the base is added in the form of asimple keel 85 to ensure the capsule is self-righting.

Three feet 86 are attached close to the corners of the base. These aremade of a firm but compressible foam such as polyethylene, whichprovides shock absorption when the capsule is landed. The triangulararrangement of the feet ensures that the capsule will be as stable aspossible when standing on an uneven surface.

The advantages of the invention are that the rigid cage of the capsuleprotects personnel and/or cargo from any direct impacts during transfer;personnel and cargo are secured in position by harness during transfers;personnel and cargo are protected against impact loads on the capsule byshock absorption in seating and shock absorption built onto the exteriorof the capsule; the capsule is buoyant when loaded to prevent personnelor cargo becoming permanently submersed, if landed in water; and, thecapsule is self righting when immersed in water to prevent personnel orcargo suffering prolonged submersion due to the orientation of thecapsule in the water. In addition, the feature of a compensated landingsystem in the form of a sprung member in the suspension gear of the load(personnel carrier or otherwise) has the advantage of providing morecontrol over the transfer operation. This system allows the load to belifted from and landed onto the deck of a vessel while the supportingline remains in tension. This helps prevent the load being struck as aresult of the relative upward motion of the vessel deck.

Advantages of the systems disclosed above over existing transfer systemsare the rigidity, inherent strength, convenient shape and itsself-righting characteristics, buoyancy and stability in water. Thecapsule is also stable when landed on an uneven surface such as the deckof a vessel at sea. These properties arise from the shape of the capsuleand the positioning of buoyant material within this shape.

Also, the invention has the advantage of being able to provide sprungseating and provision for the attachment of a stretcher which offerprotection against impact loading for personnel and freight duringtransfer.

Furthermore, the simple shape of the capsule is economical tomanufacture using established moulding or fabricating techniques, andthe profiled shape of the capsule reduces the chances of its hanging upor becoming caught on structures or obstacles whilst in use.

We claim:
 1. Apparatus for transferring objects from a first location toa second location, where the locations are horizontally spaced, theapparatus comprises a transfer device adapted to be coupled to a liftingdevice, the transfer device comprising a central load bearing memberwhich is adapted to be coupled to the lifting device, an outer structurewhich defines an inner space in which an object to be transferred may belocated, the outer structure being coupled to the central load bearingmember, and securing means to secure the object in the inner space ofthe transfer device during transfer, the securing means being coupled tothe central load bearing member, and the securing means being spacedapart from the outer structure, the transfer device further comprisingbuoyancy means, wherein the transfer device is self-righting when inwater.
 2. Apparatus according to claim 1, wherein the object to betransferred is a person and the securing means comprises a seat and aharness.
 3. Apparatus according to claim 1, wherein the outer structureis a cage.
 4. Apparatus according to claim 1, wherein the buoyancy meanscomprises a substantially rigid closed cell material.
 5. Apparatusaccording to claim 1, wherein the transfer device includes shockabsorbing means to absorb impact of the transfer device with otherobjects.
 6. Apparatus according to claim 5, wherein the apparatus alsoincludes a guideline coupled between the transfer device and the secondlocation to guide the transfer device to the second location. 7.Apparatus according to claim 5, wherein the shock absorbing meansincludes shock absorbers on a base of the outer structure to absorb theshock of landing.
 8. Apparatus according to claim 5, wherein the shockabsorbing means includes second shock absorbing means mounted betweenthe securing means and the outer structure, so that the securing meansis coupled to the outer structure by the second shock absorbing means.9. Apparatus according to claim 8 wherein the apparatus also includes athird shock absorbing means coupled between the transfer device and thelifting device.
 10. Apparatus according to claim 8, wherein the securingmeans is slidably mounted on the central load bearing member by thesecond shock absorbing means.
 11. Apparatus according to claim 5,wherein the outer structure comprises a base section and a number ofside walls, the side walls extending from the base section to a commonapex, the base section and the side walls defining the inner space. 12.Apparatus according to claim 11, wherein the base section has apolygonal shape.
 13. Apparatus according to claim 12, wherein the shapeformed by the base section and the side walls is generally the shape ofa pyramid.
 14. Apparatus according to claim 13, wherein the pyramid is atriangular pyramid or tetrahedron.
 15. Apparatus according to claim 11,wherein the outer structure is coupled to the central load bearingmember at the common apex and the base section of the outer structure.16. Apparatus according to claim 11, wherein the buoyancy means includebuoyancy material mounted on the side walls, and the base section. 17.Apparatus according to claim 11, wherein the buoyancy means includebuoyancy material mounted on the said common apex.